Monday, November 28, 2011

Night Stand

I wanted to show you what I did with the table top that was used to try different spraying techniques. The center of the top is ash veneer on plywood and the surrounding wood is a figured cherry veneer on plainsawn cherry. I ran out of cherry for the legs and was wondering how close I could match the color using poplar. I sprayed the same red dye as I had used on the cherry, then sealed it by spraying with clear shellac. Finally, I used a water-based finish. The whole finishing process took less than three hours of which two and half were waiting for the wood to dry.

The wood surface on the legs is a little rougher than I want. The water in the dye has caused some of the wood fibers to raise. I could have tried sanding it lightly after applying the shellac, but I was concerned about removing some of the stain. Next time I will first spray the wood with water and sand it smooth after it dries.

I'm please with the poplar and feel that I could have applied veneer over it on the table top and saved some money.


Monday, November 21, 2011

Cleaning a spray gun in 3 minutes

When I first investigated HVLP spray guns I was apprehensive about cleaning them. It sounded like you needed a fairly large project to justify the time and hassle of maintaining the gun. I have two gravity type guns, a full size one with a 20oz cup and another gun with a small 4oz cup intended for detail or repair work. The small gun is more than sufficient for 90% of my spraying jobs and the bonus is that I can clean it in less than 3 minutes.

So far, I'm have only used the small gun for spraying water-based dye and water-based finish. On my projects, I typically spray dye first and after it dries (usually in less than 30 minutes) I then spray Bulls Eye Clear Shellac to protect the dye from the water-based finish. While I could spray the shellac with gun, for most small projects, I use the Bulls Eye spray can. Finally I use the small gun to spray two coats of Minwax Polycrylic.

 Cleaning the Air Cap, Needle, Nozzle, Cup, and Gun body

These are the steps I take to clean my gun after using it to spray water-based dye and finish. I usually have a milk container filled with water and a plastic bowl that I clean over.
  1. Remove the air hose from the sprayer
  2. Pour left over dye or finish back into their containers.
  3. Rinse out the cup several times with water.
  4. Fill the cup with a couple ounces of water and pull the trigger until the dye or finish has drained and only water is being passed through the gun. You may want to back the needle off to make this faster.
  5. Remove the air cap. Run some water over it to clean.
  6. Remove the nozzle. Run some water through it from the back. Blow some air through it from your mouth. Looking through it from the back, verify that there are no obstructions.
  7. Run some more water through the gun. This will clean the cavity in the gun body.
  8. Whip the cup dry with a paper towel. Sometimes you may see a residual color on the cup from the dye. Dampen a paper towel with alcohol and whip the color off.



Sunday, November 20, 2011

Table Top Re-visited

Finished Table Top
I wanted to apply the technique I previously posted to this table top. Two wood veneers have been used, ash and figured cherry. I wanted to dye stain the ash a light brown color and the cherry red. I spray the dye to get uniform coverage. The challenge is controlling the spray so that it doesn't stain the wrong wood. I accomplish this by masking the wood, just as you would when painting.
To highlight the grain of the ash, I first applied a gel stain. Details about this are in a previous post. The next step is masking the ash with tape and then spraying the surrounding cherry with a red dye. I use water-based dyes made using Homestead's TransTint. Straight lines are easy to tape but the curve looked to be difficult.

Luckily, I had cut another curved section to help glue the top together. I used this as a template for cutting the tape with a knife. This made taping the curved sections easy.

I covered the remainder center of the taped section and then sprayed the red dye on the cherry. I remove the tape immediately so that there would be less chance of the red dye soaking under the tape. As I discuss in my previous post, spraying a mist of dye makes it dry immediately. After the dye completely dried, I applied tape over the cherry and sprayed the ash with a brown dye.

I again removed the tape immediately, and after the ash dried, I sprayed a light coat of shellac to protect the dye from the water-based finish. The final step was to spray the Minwax Polycrylic and then I was done. The top photo shows the finished top.

Wednesday, November 16, 2011

Dye Staining Update

Sample board with two stains
When using several wood species in a project, different colored dye stains may be required. I needed to do this for a tabletop that was ash surrounded by cherry. It would have been easy to stain each wood before gluing. When touching the tabletop, I didn't want any bump between the ash and the cherry. This meant that I may have to sand the bump but then the stain that was applied would be destroyed. I chose to stain the wood after gluing.

Staining two areas side by side is a challenge. My earlier post suggested using tape to mask areas not to be stained. This seems to work however if the sprayed dye is too wet, it can seep under the tape, as shown in the circles here.

I decided to do another spray test. For my test board, I've taken veneered ash and cut it into three pieces. I glued two pieces on the right together with the grain running the same direction. The piece on the left was rotated 90 degrees and glued. The image at top shows the sample board.

My goal is to stain the middle section brown and the sides red. I like to spray dye for consistent results as I described in a previous post. To keep the dye from seeping under the tape, the spray gun was adjusted to create a very light mist. This mist doesn't even form drops on the wood surface and it dries quickly within minutes. To get a darker shade of stain, just spray it again. If needed, dampen a small section of the stained wood with mineral spirits or naphtha to see what shade the stain will have when covered by a finish.

I was able to get a light mist on my HVLP gun by using a 0.8mm nozzle, adjusting the needle so that only a small amount of dye would get atomized, and using just enough air pressure for atomization. After achieving the shade that I wanted on the middle section, I sprayed it with Bulls Eye Clear Shellac. To save time, I just use their can of spray for small projects.

On my previous post, I had said the shellac will effectively mask the wood from the application of the second dye. After further experimentation, I have decided that I can't recommend doing this. A slight tint from the second dye remains on the shellac. On this sample, I used tape to mask the middle section and using the red dye, I repeat my light mist spraying on the exposed wood. When done, spray with shellac, and after removing the tape, lightly spray the shellac again along where the edge of the tape was. This ensures the dye is completely protected from the water-based finish.





Thursday, November 10, 2011

Mission Style Finish Recipe

My computer desk
I'm really attracted to the Mission Style finish. The character of the wood is really highlighted by this stain treatment. I use quarter-sawn white oak, the traditional wood used in mission style furniture. Cutting wood quarter-sawn reveals an immense pattern of rays and flakes in oak. Their undulating pattern is accentuated by a pigment stain. An additional dye stain gives the wood your desired shade of brown. Traditionally, staining the wood was performed by exposing it to strong ammonia fumes. I tried this once and became the least favorite member of the family.

Over many years, I have created a multiple step process that works reliably. As I have said in previous posts, I tend to use veneer. It is much more affordable and available than solid wood. I purchase my veneer online from Certainly Wood.

Here are the steps and an explanation of why are done.
  1. Sand the wood surface until you reach 180 grit. There is no reason to go finer.
  2. The pattern in the wood is highlighted by creating contrast between the grain and the wood surface. I use a Mahogany colored Minwax Gel Stain to embed a dark pigment in the grain. Use a disposable glove and spread clumps of stain on the wood. Almost immediately, take paper towels and remove the excess stain on the wood surface by wiping across the grain. This leaves the pigment in the grain and leaves the wood surface almost the same color as what you started with.
  3. Let the gel stain dry for 8 hours or until it's solvent can't be smelled.
  4. Preferably using an orbital sander, use 220 grit sandpaper to remove the stain color from the wood surface. The pigment stain will remain in the grain which is below the surface. You want to color the surface with the water-based dye stain. I like to use Homestead's TransTint. They have many brown shades located here.
  5. Apply a dye stain either by spraying or wiping it on the surface. Spraying is faster but I've wiped it on for many years. I pore a little on and spread it lightly with a 3M maroon colored Scotch-brite pad. You want the get the surface universally wet with thin film of dye. Let the dye dry without wiping it off. This will give it a uniform appearance, as long as you didn't leave puddles of dye liquid on the wood.
  6. The dye usually drys within a hour. Spray it with Bulls Eye Clear Shellac to protect the dye from later steps.
  7. After the shellac drys (usually in minutes), feel the surface for smoothness. Sometimes the water in the dye will raise the wood fibers. Lightly sand them off using a maroon pad. Don't bare down which may remove the stain.
  8. Now you are ready for a finish to protect the wood and the stain. The shellac you applied will protect the stains from most finish treatments. I like to use a water-based satin finish. The satin sheen lowers any glare from light reflecting from the wood surface which obscures the grain. I use Minwax Polycrylic Satin Finish. I'll spray Polycrylic deluded 10% with distilled water. Deluding it makes it easier to spray. Let it dry for several hours and feel if the surface is smooth. If so, spray it one more time and you are done. If its a little rough, wait overnight and sand the surface lightly with 220 grit sandpaper, just enough to remove the rough spots. Spray it again, and then you are done.
I'm sure this seems like many steps but the end product is worth the effort.

Tuesday, November 8, 2011

Spraying dye for consistent results

Dyes are made up of molecular-size particles that add color to wood without loss of grain definition. Because dyes are transparent, they enhance the figure of the wood. Tight grain woods like maple and birch can only be successfully stained by using dye. Most stains that you can purchase from local home stores use pigments. These are made up larger particles that enhance the wood's grain because they get lodged in the pores.

I like to use TransTint dyes made by Homestead Finishing. I mix them into water and apply. Using a rag, it's easy to get lap marks if the dye is drying too fast as you apply it. I've been successful poring a small puddle on the wood and using a 3M maroon colored Scotch-Brite very fine abrasive pad to spread the dye quickly over the entire surface. I make sure there isn't any puddles, and then just let the wood soak in the dye and let it dry. In most cases, this works well. Lately, I've been spraying dye for a more reliable outcome.

Here is my new toy. It's a small HVLP sprayer intended for detailed or touch-up applications. With a 4 ounce cup capacity, this sprayer is more than enough for many of my projects. A major bonus is that it only takes a minute to clean the gun. To spray dye without getting the drips that cause lap marks can be a challenge because the low viscosity of water is difficult to atomize. You want a gentle mist of dye to apply to the wood so puddles don't occur. The lower the viscosity of the finish you are spraying, the smaller you want the nozzle diameter to be. I have found that a 0.8mm nozzle works perfectly for dye.

I know you are thinking, this is something for someone more talented, or at least more rich, than me. I've looked at spray guns for years and they are either very expensive or very cheap. The cheap ones must be bad, otherwise why do people buy expensive ones? There must be a difference that professionals can claim, but I found a inexpensive gun that delivers great quality for under $30.  Here is a source for the same product that I purchased.

Combined with my inexpensive Husky compressor ($99), I am ready for even more new projects. Now I spray dyes, shellac, water-based finishes, and even acrylic paint. I'll never go back to brushes. I'll expand on this in later posts.


Sunday, November 6, 2011

Cutting veneer easier

Using a shooting plane to cut veneer
The cost of quality wood has driven me to use veneer for many of my projects. Veneer has a bad reputation of being inferior to solid wood. When veneer is glued to MDF or cabinet grade plywood, it has none of the warpage and expansion/contraction of solid wood. Buying veneer online is an easier prospect than getting high quality solid wood from your local lumber distributor.


This post is about a reliable way of cutting a straight edge on veneer. Strips typically need to be positioned side by side and glued to form a wide board. The challenge is cutting straight edges on each side of a veneer strip. Typical approaches involve running a plane along the edge or passing the strip through a joiner. Both of these approaches can cause the veneer to tear out due to changes in the grain direction. I've wasted many strips of veneer trying to get the perfect edge.

Cutting from the side of the veneer causes the tear out. What I do is run the veneer on a sled through the table saw. When the veneer is supported against vertical movement, the table saw blade will cleanly cut the veneer, independent of grain direction. This sled is about 1 foot wide and is made of ¼" double sided melamine. To hold the veneer strip, short pieces of double sided adhesive tape are used.


A cross cut blade gives the best results. The blade I use has 80 teeth. Raise the blade until the entire tooth just clears the sled. The table saw fence should be moved to keep the edge of the sled barely touching the blade. No gap reduces the chance of tearing the veneer.


Position the veneer where you want the cut to occur. Use another scrape piece the length of the sled to keep the veneer flat on the sled. Run it through the fence and detach from the fence. Sometimes I use a putty knife to help pull the veneer from the tape. I've tried cutting more than one veneer strip at the same time with limited success. One at a time is more reliable. Now you have a techique for taking advantage of the economy and high quality of veneer in your projects.  

Saturday, November 5, 2011

Making cabinet glue up easier

Circle shows gap
I like to use melamine for constructing kitchen and bathroom cabinets. After cutting rabbets in the bottom and top for the cabinet sides, I run out of clamps and patience trying to glue it together. The problem is pushing sides together to eliminate any gaps from showing. I want to show you how to use biscuits to remove clamps that were needed to squeeze the sides together during glue up.

A biscuit cutter is positioned vertically on the bottom board and aligned to the side of the rabbet cut. A scrap board and using playing cards as shims allows the cutter to make slots vertical to the board surface.


Next, cut biscuit slots into the ends of the board sides referencing the bottom of the cutter with the inside of the board.







Apply glue and position the board sides within the rabbits using the biscuits to eliminate any gap. Only vertical clamps are needed to ensure a good bond.

Staining two different wood species

A sign of fine woodworking is pairing several wood species together in a project. Here I am making a tabletop using two veneers, ash and cherry. The challenge I frequently have is getting the two different species to be exactly flush. There should be no bump when running your finger across the glue line. I typically use a biscuit joiner to align the tops before gluing, but the finger is sensitive to any bump. I've come to the conclusion that I have to allow for light sanding. But this will prevent me from staining the pieces before glue up.

To accent the pores in the ash, I have applied Minwax Gel Stain Honey Maple. Using a paper towel, I wipe the gel off across the grain. This leaves the colored stain in the pores. Lightly sand the ash using 180 grit sandpaper after the stain has dried. If you can smell the solvent from the stain, then it's still drying. The ash will be dyed after glue up.

After gluing the pieces together, I lightly sand the surface with 180 grit to make the top perfectly smooth. The ash needs to be dyed a light brown and the cherry a light red. I use water based dyes made using Homestead's TransTint. The problem is keeping the dyes from staining the wrong species. I masked the cherry with tape and sprayed the ash with the dye and after it dried, I sprayed a thin coat of Bulls Eye Clear Shellac.

The tape did a great job of protecting the cherry from being dyed. Next I need to apply the red dye. Rather than having to cover the ash with tape, the shellac will prevent the red dye from being absorbed. See how it beads up on the ash. Simply wipe it up with a paper towel.


Let the red dye dry and spray it with shellac. Even after the dye has dried, a water based finish can ruin it, so the shellac creates a barrier between the two. Finally, spray a coat of Minwax Polycrylic on the surface. Let it dry for several hours and run your hand across the surface. Any small bumps can be leveled using a 3M gray colored Scotch-Brite ultra fine pad.

One more coat of Polycrylic and then you have a smooth table top you can be proud of.